This invention relates to a vane groove grinding apparatus for a compressor cylinder containings an inner hole and a vane groove extending radially outwardly from the inner hole.
FIG. 8 is a perspective view showing a conventional vane groove grinding apparatus in which a compressor cylinder 1 held in the shown position by a holding means (not shown) has an inner hole 2 (center line: O1) and a vane groove 3 extending radially outwardly from the inner hole. In the inner hole 2, a holder 5 and a thin cylindrical inside grinder 6 are inserted, the holder 5 being attached on the left end of a grinding apparatus, a right end of the grinder 6 being connected to a spindle 7 and the left end of the grinder 6 being rotationally received by the holder 5. While keeping the grinder 6 in high speed rotation by the spindle 7, when the body 4 is driven in the direction of arrow X1 together with the grinder 6, the grinder 6 grinds one surface of the opposing surfaces of the groove 3, and when the body 4 is driven in the reverse direction from arrow X1, the grinder 6 grinds another surface of the opposing surfaces of the groove 3. 8 is an open space. Generally in the vane type compressor, the cylinder 1 is covered by side housings from both sides, and a rectangular vane plate in the groove 3 contacts on the outer surface of an eccentric rotor (not shown).
But, according to the above grinding system, abrasion on the grinder 6 differs at places of different distances from its proximal end, which causes the deterioration of plane degree (accuracy) and parallel degree (accuracy) of the opposing surfaces of the groove 3. In addition, due to the small diameter of the grinder 6, its grinding speed on the surface and its rigidity are inevitably low, these disadvantages increase as the width of the groove gets small.
In a disk grinding system shown in FIG. 9, a grinding disk 10 supported by a bar-shaped holder 9 and driven in the direction of arrow X2 by way of a drive force transmitting means installed inside the holder 9, grinds one surface of the opposing surfaces of the groove 3 when the holder 9 moves to the left in the direction of arrow X2, and grinds another surface of the groove 3 when the holder 9 returns in the reverse direction to the position of FIG. 9.
But, according to the grinding system of FIG. 9, since the projecting distance of the holder 9 varies as the grinding process proceeds and the holder 9 is a cantilever the plane degree and parallel degree of the opposing surfaces of the groove 3 are inevitably unstable. In addition, it is difficult to change the grinding disk, in that it is necessary to change the grinding disk 10, belts, bearings and the like.
An object of this invention is to improve manufacturing accuracy, especially for plane degree and parallel degree, and manufacturing efficiency. A first embodiment is a vane groove grinding apparatus for a compressor cylinder comprising a compressor cylinder holding means, the compressor cylinder being provided with an inner hole and a vane groove extending radially outwardly from the inner hole, sliders being movable along a center line of the inner hole and along a right angled direction to the vane groove, a grinding disk holder facing one open side of the inner hole and a support for locking said holder facing another open side of the inner hole both being disposed on a slider adjacent to the compressor cylinder, when the grinding disk is inserted in the vane groove a distal end of the grinding disk holder is firmly engaged in the support.
A second embodiment is a vane groove grinding apparatus as described above, in which the compressor cylinder holding means is an index table being provided with a plurality of working stations at regular intervals with clampers.
A third embodiment is a vane groove grinding apparatus of the type of the first embodiment, in which one of the engaging portions of the holder and support is a wedge shaped projection and another portion is a wedge shaped slot.
A fourth embodiment is a vane groove grinding apparatus of the type of the first embodiment, in which the sliders are composed with combined plural sliders.